Comparison of cytotoxic and apoptosis-inducing effects of MTA, propolis, and propolis-MTA on immature dental pulp stem cells

BACKGROUND

Pulpotomy is a treatment option for the preservation of pulp vitality in primary teeth with extensive caries. Propolis is a natural resinous substance with optimal antimicrobial, anti-inflammatory, and immune-regulatory properties. Thus, this study aimed to compare the cytotoxic and apoptosis-inducing effects of mineral trioxide aggregate (MTA), propolis, and MTA-propolis on immature dental pulp stem cells (IDPSCs).

METHODS

In this in vitro, experimental study, primary IDPSCs were exposed to propolis, MTA, and MTA-propolis for 24 and 72-h. The cytotoxicity and apoptosis-inducing effects were evaluated using the methyl thiazolyl tetrazolium (MTT) assay and flow cytometry, respectively. Data were analyzed using ANOVA and Tukey's test at 0.05 level of significance.

RESULTS

The cytotoxicity of MTA and MTA-propolis was higher than that of propolis alone at both 24/48 h. In addition, all tested concentrations showed higher biocompatibility at 72-h compared with 24-h (P < 0.0001). In the assessment of apoptosis, propolis-MTA showed higher cell viability compared with other materials (P < 0.0001).

CONCLUSION

Propolis-MTA showed higher biocompatibility than MTA. Addition of propolis to MTA improved cell proliferation in the first 24-h. Also, the cytotoxicity of propolis was lower than other materials in the first 24-h. Thus, propolis may serve as a promising pulp capping agent given that its other properties are approved.

Probing nanoliposomes using single particle analytical techniques: effect of excipients, solvents, phase transition and zeta potential

There has been a steady increase in the interest towards employing nanoliposomes as colloidal drug delivery systems, particularly in the last few years. Their biocompatibility nature along with the possibility of encapsulation of lipid-soluble, water-soluble and amphipathic molecules and compounds are among the advantages of employing these lipidic nanocarriers. A challenge in the successful formulation of nanoliposomal systems is to control the critical physicochemical properties, which impact their in vivo performance, and validating analytical techniques that can adequately characterize these nanostructures. Of particular interest are the chemical composition of nanoliposomes, their phase transition temperature, state of the encapsulated material, encapsulation efficiency, particle size distribution, morphology, internal structure, lamellarity, surface charge, and drug release pattern. These attributes are highly important in revealing the supramolecular arrangement of nanoliposomes and incorporated drugs and ensuring the stability of the formulation as well as consistent drug delivery to target tissues. In this article, we present characterization of nanoliposomal formulations as an example to illustrate identification of key in vitro characteristics of a typical nanotherapeutic agent. Corresponding analytical techniques are discussed within the context of nanoliposome assessment, single particle analysis and ensuring uniform manufacture of therapeutic formulations with batch-to-batch consistency.

Non-syndromic multiple odontogenic keratocyst: a case report

Odontogenic keratocyst (OKC) is a common developmental odontogenic cyst affecting the maxillofacial region. Multiple OKCs are usually seen in association with nevoid basal cell carcinoma syndrome (NBCCS) but approximately 5% of patients with OKC have multiple cysts without concomitant syndromic presentation. This report represents a case of multiple OKCs in a non-syndromic patient.

First microscopical and molecular-based characterization of Leishmania major within naturally infected Phlebotomus salehi (Diptera; Psychodidae) in Fars province, southern Iran

Zoonotoc cutaneous leishmaniasis is endemic in several parts of Iran. Jahrom district is one of the most important endemic foci of leishmaniasis located in Fars province, southern Iran. To identify the vectors of leishmaniasis in this area, a total of 349 sandflies were collected during May to August 2009. They were caught from outdoors in five regions of Jahrom district including villages of Mousavieh, Ghotb-Abad, Heydar-Abad, Fath-Abad and Jahrom County. Eleven species of Phlebotomine (three Phlebotomus spp. and eight Sergentomyia spp.) were detected. To determine the sandflies naturally infected by Leishmania spp., 122 female sandflies were dissected and evaluated microscopically using Giemsa-stained slides. Natural infection of 2 out of 38 (5.26%) P. papatasi and 1 out of 8 (12.5%) P. salehi to Leishmania major was confirmed in the region. Sequencing and nested polymerase chain reaction-based detection of Leishmania were carried out to confirm the microscopic findings. Five (13.16%) P. papatasi and two (25%) P. salehi were positive in nested polymerase chain reaction assay. All positive samples were shown 72-76% similarity with L. major Friedlin. On the basis of our knowledge, this is the first molecular detection of L. major within naturally infected P. salehi in this region in southern Iran.

Trucut biopsy of breast lesions: the first step toward international standards in developing countries

The new concept in breast cancer diagnosis and treatment is based on a less invasive, more accurate and effective strategy, with a multidisciplinary approach in a specialised breast unit. When indicated, conservative surgery has replaced mastectomy with sentinel-node biopsy substituting routine axillary dissection. But the key factor in respect of these new standards is to confirm the cancer before going to the operating room. Trucut biopsy is performed instead of incisional or excisional biopsy and frozen section. The technique is reliable, simple, and reproducible, and not at all expensive; it can be adapted even for low-income developing countries.

MATERIALS AND METHODS

Between March 2006 and June 2010, 764 patients under clinical suspicion of cancer and/or with BIRADS (Breast Imaging Reporting and Data System) III-V in imaging in one university and one private hospital in Tehran, Iran underwent trucut biopsy (60% palpable and 40% non-palpable lesions). Cancer was found in 30.8% of the cases. In benign pathology, in concordance with clinical and imaging suspicion, surgery was omitted with short-term follow-up. For palpable symptomatic benign lesions surgery was performed to relieve the patient's symptoms. When the pathology report was not in concordance with clinical/imaging suspicion (1.8%), and in the presence of moderate and severe hyperplasia with or without atypia, in lobular and papillary lesions (4.9%) open biopsy was done to rule out cancer (10 added cancers, 1.3%; total cancers 32.1%). Cancer surgery was done as a single procedure in 89.8% of cases.

CONCLUSION

Trucut biopsy for breast lesion assessment is the first step toward a new concept in breast cancer care. It is simple, reduces the number of surgeries (no surgery for non-symptomatic benign lesions and one surgery for cancer), and avoids diagnostic errors with full respect for the patient's rights. We insist on its routine use to extend international guidelines while decreasing the total cost of this common disease in all low-resource countries.

The PCR-based detection and identification of the parasites causing human cutaneous leishmaniasis in the Iranian city of Ahvaz

In Iran, Leishmania major or L. tropica cause almost all of the human cutaneous leishmaniasis (CL). Unfortunately, the detection methods frequently used for CL (the microscopical examination of direct smears or the culture of biopsies) are not very sensitive and the Leishmania species causing each case of CL in Iran is usually only tentatively identified from extrinsic factors, such as the case's clinical manifestations and region of residence. Recently, however, a nested PCR that targets the parasites' kinetoplast DNA has been used in the city of Ahvaz (the capital of the province of Khouzestan, in south-western Iran) to confirm the microscopical diagnosis of CL and to identify the causative parasites, to species level. Smears from the lesions on 100 suspected cases of CL were fixed, stained with Wright's eosin-methylene blue, and checked for amastigotes under a light microscope. Scrapings from the same smears were then tested for leishmanial DNA, using a nested PCR that allows the DNA from L. tropica to be identified and distinguished from that of L. major. The 100 smears investigated were all found amastigote-positive by microscopy and PCR-positive for either L. major DNA (97 smears) or L. tropica DNA (three smears). The predominant species causing CL in Ahvaz is therefore L. major.

Comparison of three methods for diagnosis of cutaneous leishmaniasis

BACKGROUND

Leishmaniasis is one of the infectious parasitic diseases of highest incidence in the world. Cutaneous Leishmaniasis (CL) has long been reported in Shiraz, Southern Iran. There is a need to find a sensitive and specific method for treatment and control of the disease.

METHODS

We have compared the sensitivity of the conventional methods microscopy and cultivation of lesion scrapes against PCR amplification of parasite kinetoplast DNA from these samples. The samples (n=219) were obtained from the patients clinically suspected of CL. The smears were stained with Giemsa for microscopy and cultured in Novy-Nicolle-McNeal (NNN) blood agar for promastigote growth. For PCR, the dry smears were scraped off the slides and DNA was extracted.

RESULTS

The positive rates from 219 specimens were 76.71%, 50.68%, and 93.61% for microscopy, cultivation, and PCR, respectively. The highest correlation was found between PCR and microscopy method (P=0.014). In PCR assay, 95.61%, 3.9%, and 0.49% of the samples were identified as Leishmania major, L. tropica, and dermatropic L. infantum, respectively.

CONCLUSION

The PCR method appears to be the most sensitive for the diagnosis of CL and is valuable for identifying the other species of Leishmania with confusing dermatropic signs.

Behavioural and emotional problems in Iranian children four years after parental death in an earthquake

BACKGROUND

Although previous research has established a direct impact of natural disasters on child mental health, there is limited knowledge on the underpinning mechanisms, particularly when there has been the loss of a parent.

AIMS

To establish: (a) the rates of behavioural and emotional problems of school-aged children who had lost their parents in the 2003 earthquake in Iran, compared with children from intact families who attended the same schools; (b) the relationship between the psychopathology of the surviving parents' and children's behavioural and emotional problems; and (c) whether this relationship was compounded by socioeconomic factors.

METHODS

Eighty six children of 7-13 years who had lost a parent in the earthquake four years earlier were compared with 80 matched children from intact families. The teacher and parent versions of the Strengths and Difficulties Questionnaire (SDQ) were used as measures of behavioural and emotional problems. Parents' psychopathology was established by the Self Report Questionnaire (SRQ).

RESULTS

Behavioural and emotional problems were significantly higher in children who had suffered parental loss than in the control group. There was a significant association between parent-rated SDQ and SRQ scores. Parental death was found to interact with socioeconomic variables in predicting children's behavioural and emotional problems and surviving parents' mental health problems.

CONCLUSIONS

After natural disasters, bereaved children and their surviving parents are at risk of developing mental health problems, and social adversities increase this risk.

Chrysomya bezziana as a Causative Agent of Human Myiasis in Fars Province, Southern Iran

Myiasis is the invasion of body tissues of humans or animals by the larvae of the Diptera or two-winged flies. The various forms of myiasis may be classified from clinical or entomological point. This study describes the existence of Chrysomya bezziana (Diptera: Calliphoridae) cases as a causative agent of myiasis in 18 and 87 year-old men in two different regions in Fars Province. To our knowledge, this is the first observation of mentioned species in this province.

Asymptomatic human carriers of Leishmania infantum: possible reservoirs for Mediterranean visceral leishmaniasis in southern Iran

Over the last decade, the incidence of visceral leishmaniasis (VL) has increased in many districts of the province of Fars, in southern Iran. Recent epidemiological reports indicate that asymptomatic human infections with Leishmania infantum (the causative agent of VL throughout the Mediterranean basin) occur more frequently in Iran than was previously believed. Between 2004 and 2006, blood samples were collected from 802 apparently healthy subjects from communities, in the north-west and south-east of Fars province, where VL cases had been recorded. Each of these samples was tested for anti-Leishmania antibodies, in direct agglutination tests (DAT), and for L. infantum kinetoplast DNA, in PCR-based assays. Of the 426 subjects from north-western Fars, eight (1.9%) were found seropositive and 68 (16.0%) PCR-positive. The corresponding values for the 376 subjects from south-eastern Fars were lower, with five (1.3%) seropositive and 32 (8.5%) PCR-positive. Of the 100 PCR-positive subjects, 18 (18.0%) each lived in a household in which there had been a case of VL, and six (6.0%) had had VL themselves (in each case, more than a year before the blood sampling for the present study). Although 21 of the PCR-positives have now been followed-up for at least 18 months, none has developed symptomatic VL. Since positivity in the PCR-based assay probably indicated the presence of L. infantum amastigotes in the peripheral blood of 12.5% of the subjects, it is clear that asymptomatic human carriers of L. infantum are quite common in the study areas and probably act as reservoirs in the transmission of the parasite, to humans and to dogs, by sandflies.

Multidisciplinary intervention for reducing malnutrition among children in the Islamic Republic of Iran

A multidisciplinary intervention to reduce protein-energy malnutrition among children in rural areas was piloted in 3 provinces of the Islamic Republic of Iran. Based on an initial situation analysis, a range of interventions were implemented through local nongovernmental organizations, including nutrition, health and literacy education for mothers, improved growth monitoring and fostering rural cooperatives and income generation schemes. Malnutrition before and after the intervention (in 1996 and 1999) was assessed using anthropometric measurements of random samples of children aged 6-35 months in control and intervention areas. Three years into the intervention, all indicators of malnutrition had consistently decreased in all intervention areas and the prevalence of underweight and stunting was significantly lower. Control areas showed a mixed pattern of small increases and decreases in malnutrition indicators.

Typing of human papillomavirus by pyrosequencing

The possibility of using a new bioluminometric DNA sequencing technique, called pyrosequencing, for typing of human papillomaviruses (HPV) was investigated. A blinded pyrosequencing test was performed on an HPV test panel of 67 GP5+/GP6+ PCR-derived amplification products. The 67 clinical DNA samples were sequenced up to 25 bases and sequences were searched using BLAST. All of the samples were correctly genotyped by pyrosequencing and the results were unequivocally in accordance with the results obtained from conventional DNA sequencing. Pyrosequencing was found to be a fast and efficient tool for identifying individual HPV types. Furthermore, pyrosequencing has the capability of determining novel HPV types as well as HPV sequence variants harboring mutation(s). The method is robust and well suited for large-scale programs.

Overrepresentation of point mutations in the Sp1 site of the non-coding control region of BK virus in bone marrow transplanted patients with haemorrhagic cystitis

BACKGROUND

Haemorrhagic cystitis (HC) in allogeneic bone marrow transplanted (BMT) patients is associated with reactivation of BK virus (BKV) manifested as BK viruria. However, it has been suggested that BKV reactivation alone is not responsible for HC, since BKV can be detected in the urine of 50-90% of all adult BMT patients.

OBJECTIVES

In the present study, we analysed if BK viruses with specific mutations in the non-coding control region (NCCR) or in the region encoding the major capsid protein (VP1) were more frequently associated to the appearance of HC in BMT patients.

STUDY DESIGN

The NCCR and the region encoding VP1 of BKV excreted in the urine from 25 BMT patients, 16 with and nine without HC, were sequenced by an ABI Prism Big Dye terminator cycle sequencing ready reaction kit.

RESULTS AND CONCLUSIONS

A statistically significant (P=0.019) overrepresentation of C to G mutations within the NCCR Sp1 binding site was observed in 7/16 (43%) patients with HC (six cases at position 249 (P=0.035) and one case at position 251), as compared with 0/9 (0%) of the patients without HC. Major differences were not observed in the VP1 sequences of patients with and without HC. BKV WW and WWT-variants as well as BKV subtype I were most commonly encountered in both groups of patients. In conclusion, C to G point mutations, within the BKV NCCR Sp1 binding site, were significantly more common in patients with HC, suggesting that these mutations may be indicative for the clinical diagnosis of HC and could influence the virulence of the virus.

Physical state of HPV16 and chromosomal mapping of the integrated form in cervical carcinomas

Using a procedure based on restriction enzyme cleavage, self-ligation, and inverse polymerase chain reaction (rliPCR), the authors investigated 18 cervical intraepithelial neoplasia III (CIN III) cases and 37 invasive squamous carcinomas for integration of human papillomavirus type 16 (HPV16). All eighteen CIN III cases (severe dysplasia or high-grade squamous intraepithelial lesion) were found to harbor episomal HPV, but one of the samples contained mixed episomal and integrated forms. Seventeen of 37 invasive cervical carcinoma samples were identified previously as containing the completely integrated HPV16 genome by using PCR covering the entire E1/E2 gene, and this was confirmed by rliPCR in 16 cases. One case, however, showed a low level of episomal deoxyribonucleic acid in addition to the predominant integrated form. Of the remaining 20 carcinoma samples showing episomal forms in the previous analysis, 14 were found to contain integrated forms using rliPCR, and four contained multimeric episomal forms. Thus, in total, 31 of 37 of the carcinomas (84%) showed the integrated HPV16 genome. The rliPCR product from five carcinoma cases was cloned into a plasmid vector and used as a template for "primer walking" deoxyribonucleic acid sequencing to deduce human sequences flanking the integrated HPV genome. Based on this information, bacterial artificial chromosome (BAC) and P1-derived artificial chromosome (PAC) clones were obtained and used as probes in fluorescent in situ hybridization experiments on human metaphase chromosomes. The results of the fluorescent in situ hybridization experiments showed evidence for HPV16 integration in chromosome regions 1q25, 3q28, 6p25, 11p13, and 18q22. Sixteen carcinoma samples, containing episomal HPV16, were sequenced in the long control region. Evidence for changes in E2 binding or silencer YY1 sequences was found in only two samples.

Persistence and tissue distribution of DNA in normal and immunodeficient mice inoculated with polyomavirus VP1 pseudocapsid complexes or polyomavirus

Introduction of DNA into normal and immunodeficient mice, alone or in complex with VP1 pseudocapsids, has been compared to DNA transfer by viral infection. Similar to natural infection and in contrast to plasmid alone, VP1 pseudocapsids efficiently introduced DNA, which remained for months in normal mice and possibly longer in B- and T-cell-deficient mice.

A population-based five-year follow-up study of cervical human papillomavirus infection

OBJECTIVE

The purpose of this study was to determine the long-term tendency for cervical human papillomavirus infections to persist in the general population.

STUDY DESIGN

From 500 women who participated in a 1991 population-based survey, 90 healthy women with normal results of cytologic examination (women with human papillomavirus deoxyribonucleic acid detected and age-matched control women without human papillomavirus deoxyribonucleic acid detected) were interviewed and examined 5 years later colposcopically, cytologically, and with human papillomavirus serologic testing and human papillomavirus deoxyribonucleic acid testing by polymerase chain reaction with 2 different consensus primer pairs (MY09 and MY11 and GP5(+) and GP6(+)), type-specific polymerase chain reaction, and deoxyribonucleic acid sequencing.

RESULTS

The 5-year human papillomavirus clearance rate was 92%. Only human papillomavirus type 16 infections persisted. Colposcopic impression of grade 2 cervical intraepithelial neoplasia was associated with persistent human papillomavirus 16 infection (P <.03). Human papillomavirus detection was associated with sexual history. Human papillomavirus type was the only determinant of human papillomavirus persistence.

CONCLUSION

The high clearance rates in a population-based setting with a 5-year follow-up period imply that inclusion of human papillomavirus deoxyribonucleic acid testing in population-based cervical screening programs should target persistent infection.

Low detection rate of HPV in oral and laryngeal carcinomas

The presence of human papillomaviruses (HPVs) in 38 oral and 16 laryngeal lesions (verrucous hyperplasia, carcinoma in situ and carcinomas) was investigated using the polymerase chain reaction (PCR) technique. All biopsies were fresh frozen and a set of consensus and type-specific primers was used for PCR detection and HPV typing. In oral biopsies a low proportion of HPV-positive cases was found, despite the sensitive techniques. Only one case out of 38, a carcinoma in situ was positive (2.6%). It is thought that this finding reflects a minimal presence of HPV in the oral lesions, but a transient role of virus in the induction of carcinomas cannot be ruled out. Differences in relation to other studies may be geographical and/or methodological. In laryngeal carcinomas (and dysplasias), 3 out of 16 cases were HPV positive. This frequency (19%) concurs with most other studies.

Disruption of the E1 and E2 reading frames of HPV 16 in cervical carcinoma is associated with poor prognosis

The E1 and E2 reading frames of 158 cervical carcinoma samples containing human papillomavirus (HPV) 16 were mapped using polymerase chain reaction (PCR). The reading frames were amplified using primers spanning the entire genes. Of the analyzed samples, 23% showed no amplification with the E1 primers and 29% showed no amplification with the E2 primers. There was an overlap, but not complete identity, between the E1- and E2-disrupted groups. All E1- and E2-negative samples were further analyzed with primers spanning subsections of the E1 and E2 reading frames, which together covered the entire genes. Of the 35 samples negative for E1, 11 were positive in specific amplification of the 3' end of the E1 gene. Several different subsections of E2 could be amplified from most samples negative for the entire gene (37/46). Five classes of patterns were found, in which either all subsections of the E2 gene or subsections in the 5', middle, or 3' end were disrupted. Although a variable pattern of disruption/deletion in the E1-E2 area of the HPV 16 genome was found in cervical carcinoma, the 5' end disruption was the most common one in both E1 and E2. Patients with carcinomas showing disruptions in E1/E2 had a poorer survival than those without such changes, and E1 disruptions were the most important prognostically.

Characterization of genotype-specific epitopes of the HN protein of mumps virus

The SBL-1 strain of mumps virus, grouping with genotype A on the basis of the small hydrophobic protein gene sequence, was grown in the presence of three different monoclonal antibodies. The monoclonal antibodies were directed against the haemagglutinin-neuraminidase (HN) protein and they inhibited haemagglutinating activity and infectivity of the virus. The HN genes of the nine neutralization-escape virus mutants were sequenced and the predicted amino acid sequences were compared with that of the parental virus. Amino acid substitutions were found at positions 269, 352 and 354, respectively, of the 582 amino acid long protein. The three monoclonal antibodies did not react with 35 virus strains isolated in Stockholm during the years 1970 to 1985. Thirteen and four of the strains were found to belong to the D and C genotypes, respectively. A type-specific neutralization antibody response was also found in sera of rabbits hyperimmunized with purified virions of genotype A and D. The genotype-specific difference in neutralizing activity in mice and rabbits was not corroborated by an overall difference in the amino acid sequence of the HN protein of the different genotypes. Further studies are needed to explore the efficacy of mumps virus vaccines for protection against homologous and heterologous genotypes of mumps virus.

Human papillomavirus findings in relation to cervical intraepithelial neoplasia grade: a study on 476 Stockholm women, using PCR for detection and typing of HPV

Among human papillomavirus (HPV) types found in humans, there is a strong association between HPV 16, 18, 31, and 33, and cervical cancer. The relationship between various grades of dysplasia and HPV type is less clear. To elucidate this point, the authors tested 476 cytological and histological samples from cervix with polymerase chain reaction (PCR) for HPV using consensus primer My 09-11 and type-specific primers. All cases were divided into groups on the basis of cytology: "normal cases" (ie, women with other disease than cervical intraepithelial neoplasia [CIN]), and CIN I, II, and III. Out of the "normal cases," in which women with a previous history of condyloma and dysplasia were included, 69% had HPV with type 6 as the most common one. Of all CIN I cases, 71% were HPV positive, and HPV type 6 and 16 were equally common. In CIN II cases, HPV 16 was the most common type, whereas HPV 6 accounted for only 7.5% of cases in this group as single virus type. HPV 16 was also the most common type in the CIN III group, followed by type 33. Double and even multiple infections occurred in all groups.

Characterization of five conserved genotypes of the mumps virus small hydrophobic (SH) protein gene

Twenty-one different mumps virus isolates from Sweden and Japan collected over 25 years were compared by nucleotide sequence analysis of the small hydrophobic (SH) protein gene, and the deduced 57 amino acid sequences of the coding part of the gene were aligned with published sequences of viral isolates from the USA, the UK, Sweden and Japan. Five genotypes were found which, in accordance with previously used nomenclature, were named A to E. Genotypes A, C, D and E were found in Europe and genotype B was found in Japan. Amino acid signature sequence motifs specific for each genotype were identified. A triplet of three amino acids at positions 28-30 was the most characteristic. Different genotypes can circulate simultaneously in a given geographical location. In Stockholm, genotypes A and D or C and D were found over different time periods. In contrast, only genotype B was found in Japan.

Use of multiple PCR primer sets for optimal detection of human papillomavirus

Using multiple PCR primer sets, we tried to optimize the detection of human papillomavirus (HPV) in DNA samples isolated from 361 frozen biopsy specimens from patients with invasive cervical carcinomas. The HPVs detected were placed into three distinct groups, including group I/Inex at Telelab (Skien, Norway) and group Ineg and group II at the Norwegian Radium Hospital (Oslo, Norway). The consensus primer sets were Oli-1b-oli-2i, My09-My11, Gp5-Gp6, and Gp(5+)-Gp6+ from the HPV L1 gene and CpI-CpIIG from the E1 gene. Using these consensus primers together with the type-specific primers from E6-E7, we found that 355 patients (98%) were HPV positive. Type-specific primers for HPV types 11, 16, 18, 31, 33, and 35 detected more HPV-infected patients than the most sensitive consensus primer set, while the three consensus primer sets My, Gp/Gp+, and Cp together detected more HPV-positive patients than the type-specific primers. Testing of sensitivity of the PCR with SiHa cells serially diluted in lymphocytes (HPV-negative cells) indicated a detection limit of 6,300 HPV type 16 DNA copies with consensus primers (My, Gp+, and Cp) and 126 original HPV type 16 DNA copies with type-specific primers. Comparison of the amplification results for consensus L1 primers and type-specific E6-E7 primers indicated the presence of L1 deletions in 23 of 56 samples. The conclusion is that in PCR detection systems, multiple consensus primers and type-specific primers should be used in order to detect all patients harboring HPV.

Human papillomavirus deoxyribonucleic acid in cervix only detected in girls after coitus

In a prospective cohort study on the prevalence of HPV in a group of female Swedish students, we obtained repeated cytological specimens during a period of 2 years, for cytological diagnosis and PCR detection of HPV. The group comprised 98 girls, sampled between 15 and 17 years, and 82 of them completed the study. The girls were also followed every sixth month by a structured face-to-face interview regarding sexuality. Only the sexually experienced girls harboured HPV-DNA in the cervix with a cumulative prevalence of 37% and HPV16 was the most common type encountered. Almost half of the infected girls were lacking any clinical or subclinical signs of HPV infection. There was a positive correlation between the presence of HPV and the number of coital partners. The time period since coitarche also had importance for the HPV detection rate.

HLA DQ-DR haplotype and susceptibility to cervical carcinoma: indications of increased risk for development of cervical carcinoma in individuals infected with HPV 18

The association of HLA class II DQB1 and DRB1 alleles with the development of cervical carcinoma was studied in 150 Swedish patients using PCR-based HPV and HLA typing. The association of cervical carcinoma with alleles encoding the DQ3 antigen, previously found among German and Norwegian patients, was not observed in the Swedish patients. Five DQ-DR haplotypes were indicated to be positively associated with development of cervical carcinoma in the Swedish patients. Two of these HLA associations were specific for HPV 18 infected patients, suggesting that the ability of the oncogenic HPV 18 to cause more rapid-transit tumors than other high risk HPV types may be due to a deficiency in antigen presentation by the HLA molecules encoded by carried on these haplotypes.

HPV-types, cytological and histopathological findings in three groups of women with possible HPV-related disease

OBJECTIVE

The aim of this investigation was to study three groups of women presenting with possible HPV-infection with regard to HPV-types and cervical dysplasia.

METHODS

Eighty women were included. Eighteen of them were present partners to men with condylomas, 20 had clinical vulvar HPV-lesions and 42 were referred due to an abnormal PAP-smear. Samples for HPV-analysis by PCR-technique were taken from the vulva, the portio and the cervical canal. A universal HPV-primer as well as specific primers for HPV 6/11, 16, 18, 31, and 33 were utilized. PAP-smears were taken as well as biopsies from cervix/portio.

RESULTS

Seventy-eight percent had HPV-DNA identified. Sixty-seven percent of those with HPV 16 and/or 18 had dysplasia verified by histopathology and 50% of those with 31 and/or 33. Twenty of 21 women with dysplasia had HPV 16, 18, 31 and/or 33 identified. One woman with dysplasia was HPV-negative. Histopathologically verified CIN were diagnosed in all groups investigated. Women referred for suspicion of CIN significantly more often had HPV detected at the cervix/portio. HPV 6/11 was mostly found in women with condylomas. Apart from this the occurrence of the different HPV types were alike in the three groups.

CONCLUSION

Infection with HPV is a process and the usefulness of different diagnostic methods seems to depend on when during the course of the disease they are used. HPV-findings in women with dysplasia were all associated with oncogenic virus-types. High-risk virus was often found simultaneously with low-risk virus indicating a covariation in the acquisition of the different HPV-types.

Implications of human papillomavirus type for survival in cervical squamous cell carcinoma

In a Swedish series of 107 invasive squamous carcinomas of the cervix, DNA extraction from paraffin-embedded material was successful in 97 cases. The prevalence of human papillomavirus (HPV) in this material was 86.6%, as determined by polymerase chain reaction (PCR) using both consensus and type-specific primers. HPV type 16 was most common (42.3%; other types were 31 (12.3%), 18 (9.3%) and 33 (10.3%). Seventeen cases (17.3%) were positive for the consensus primers only and were regarded as HPV of unknown type. There was no significant difference in corrected survival between patients with HPV-positive or -negative tumors. In the HPV-positive group, patients with tumors containing HPV 33 or HPV 18 had a significantly poorer prognosis than patients with tumors containing other types of HPV DNA (relative hazard 3.18, 95% confidence interval 1.37-7.39, P = 0.007), implying a prognostic significance of HPV type.

HPV detection in cytological cases with condylomatous or dysplastic changes: a study with PCR and in situ hybridization on cytological material

Cytobrush samples of 80 patients, who previously had a cytological or histopathological diagnosis of condyloma and/or dysplasia were investigated for human papillomavirus infection (HPV) by polymerase chain reaction (PCR) and in situ DNA hybridization technique (ISH). The results were compared with concomitantly obtained cytological Pap-stained smears or, in some cases, histological sections. The time between the diagnosis of the original and the concomitant cytology/histopathology was less than 1 yr. Six additional patients had similar morphological diagnoses 2-4 yr before. Five more cases were included on clinical diagnosis of HPV. Compared with the original morphological diagnoses, 70% of the cases were positive by PCR and/or ISH. The concomitant morphology was not diagnostic of HPV in 44 out of 80 cases (55%), showing a relatively high percentage of cases morphologically normalized in the interval since the first specimen was taken. After detection with PCR, 30 cases (37.5%) were negative for HPV. Only one of the patients with a previous disease 2-4 yr before was HPV positive by PCR and two out of five patients with a clinical diagnosis of HPV. ISH could be performed on 67/80 cases, 43 of which were positive for HPV. There was a good agreement between the results of ISH and PCR, but there were six cases positive by ISH and negative by PCR. In these cases, few infected cells may have escaped detection by PCR. Both methods seem to be able to detect silent HPV infections and comparison with concomitant cytology/histopathology shows that morphology alone is insufficient for HPV detection in these cases.

Human papillomavirus in cell samples from Stockholm Gynecologic Health Screening

We compared the results of cytologic screening of 500 women in the Stockholm Gynecologic Health Control with human papillomavirus (HPV) detection by polymerase chain reaction (PCR) and in situ hybridization (ISH). There were two main age groups, one 30 years and younger and the other 40 years and older. There were relatively more women with HPV infection in the younger group than in the older one (15.7% as compared to 11.1%), but the difference was not significant in our material. Most cases (8/12) with cytologic atypia were HPV positive by PCR. HPV type 16 was most common, followed by types 31 and 18. HPV of unknown types was detected in 43.7% of HPV-positive cases. There was excellent agreement between PCR and ISH in detecting and typing HPV.

Modifications of human and viral deoxyribonucleic acid by formaldehyde fixation

BACKGROUND

Formaldehyde reacts with human and viral DNA through interaction with hydrogen bonds, fixation of DNA-protein, and hydroxymethylation of the nucleic acids. Even though most archival tumor tissues are fixed with formaldehyde, little has been done to analyze the consequences of the reaction of formaldehyde with DNA. Misleading results can be obtained from fixed tissue using polymerase chain reaction (PCR) typing or restriction fragment length polymorphism analyses.

EXPERIMENTAL DESIGN

We have studied variations in fixation time in various tissues obtained at autopsy and in prostatic carcinoma biopsies to analyze the effects of the formaldehyde fixation. Different PCR-products were studied after different fixation times.

RESULTS

DNA from fixed tissues appears to be no more fragmented than the native DNA. Changes in the DNA structure is more important than DNA quantity for performing PCR on fixed tissues. PCR products longer than 2 to 300 bp was difficult to amplify from some tissues. Only 8 hours of fixation can be enough to inhibit amplification of more than 421 bp. Tissue fixed for longer than 215 hours cannot be amplified for more than 200 basepair products unless excessive numbers (50-80) of PCR-cycles are used.

CONCLUSIONS

The loss of PCR product is related to fixation time and PCR-product-length, probably because of the rate of denaturation followed by modification of DNA. Contrary to what has previously been assumed, formaldehyde neither fragments nor reduces the quantity of DNA, but rather changes the structure of DNA. Different tissues may also react differently with formaldehyde, in part because of different tissue fixation gradients. When the PCR product is shorter than 200 bp, DNA isolated from paraffin-embedded tissues fixed with 4% formaldehyde can be useful to any kind of PCR product analysis.

The incidence of HPV in a Swedish series of invasive cervical carcinoma

The incidence of HPV was studied in 71 invasive squamous carcinomas of the cervix using PCR technique. We used primers, which presumably recognize all types of HPV (consensus primers), and also type-specific primers. In situ hybridization was carried out in 24 of the cases. The overall incidence of HPV was 53/71 (75%) of which 5 cases were positive with the consensus primers only. However, 21/71 cases (30%) were negative for the consensus primers but positive for one of the type-specific primer pairs. This finding indicates that subgenomic deletions may have occurred in the viral genome upon integration in the human DNA. In situ hybridization was positive in 14/24 cases (58%), showing excellent correlation with PCR results. The HPV types detected were, in descending order of frequency: type 16 (52%), 31 (23%), 18 (13%), 33 (12%). No cases of HPV type 6 or 11 were found in this series of invasive carcinomas.

The acetic acid test in evaluation of subclinical genital papillomavirus infection: a comparative study on penoscopy, histopathology, virology and scanning electron microscopy findings

OBJECTIVES

To evaluate colposcopic criteria in acetowhite lesions of the penis ("penoscopy") for the diagnosis of subclinical genitoanal papillomavirus infection (GPVI) compared with histopathological criteria of HPV involvement and to various hybridisation assays for HPV DNA detection, and to depict typical lesions by scanning electron microscopy.

DESIGN

The study included 101 randomly selected male partners of females with known GPVI, or with penile symptoms such as itching, burning and dyspareunia who did not exhibit overt genital warts but appeared to be afflicted with acetowhite penile lesions after topical application of 5% acqueous acetic acid. Lesions were judged by penoscopy as either typical, conspicuous or nontypical for underlying HPV infection. Biopsy specimens from 91 men were examined by light microscopy and by either Southern blot (SB), polymerase chain reaction (PCR) and/or in situ hybridisation (ISH) assays for the presence of HPV DNA of the HPV types 6, 11, 16, 18, 31, 33 and 42 (Group A). From another ten men lesions clinically typical for GPVI were also examined topographically by scanning electronic microscopy (Group B).

SETTING

The STD out-patient clinic of the Department of Dermatovenereology of Karolinska Hospital, Stockholm, Sweden.

RESULTS

Group A Seventy eight (86%) of the biopsied lesions met the penoscopy criteria of being either typical of or conspicuous for GVPI. The agreement between penoscopy and histopathology was fairly good, as HPV diagnosis was made by both methods in 56 (62%) of the cases. The reliability of applying strict colposcopic hallmarks was further substantiated by the finding that 55 (60%) of the biopsy specimens taken from penoscopically typical/conspicuous lesions contained HPV DNA. However, there are diagnostic pitfalls for the acetic acid test. Coexistence of an eczematoid reaction with changes indicative of HPV influence was detected in six (7%) of the cases, while an inflammatory response only occurred in 17 (19%) of the specimens. Additional histopathological diagnoses (normal epithelium, lichen sclerosus et atrophicus, balanitis circinata parakeratotica, verruca plana) were established in another eight (9%) of the cases. Among the HPV DNA positive cases, all of the HPV types tested for were detected with the exception of HPV 18. A severe penile intraepithelial neoplasia (PIN III) was revealed in five (5%) of biopsies; HPV 16 was present in two and HPV 42 in one of these biopsy specimens.

GROUP B

Scanning electron microscopy depiction harmonised with the penoscopy findings showing that subclinical GPVI characteristically exhibits a well demarcated, slightly elevated border and that the central area of lesions often displays a "groove" in which the epithelium appears to be thin with protrusions from beneath that probably represent capillaries.

CONCLUSION

Use of the acetic acid test for evaluation of GPVI should be combined with a colposcopic evaluation based on strict topographic hallmarks, followed by a directed biopsy for light microscopic evaluation. We found that the positive predictive value of colposcopy was as high when correlated with histopathological findings (72%) as when virological methods were used, whether HPV DNA hybridisation testing was performed with the well established SB and ISH assays (45%), or by applying the newly introduced and highly sensitive PCR assay as well (71%). False positivity from the acetic acid test occurs and is mainly due to inflammatory conditions but also to the presence of other conditions. Epithelial fissures are evidently associated with some subclinical GPVI lesions and may potentially represent loci minores for infectious stimuli and perhaps facilitate the transmission of some blood-borne STDs. We prose that the term "papillomavirus balanoposthitis" should be used for penile HPV infection associated with inflammatory responses. Our study indicates that PIN III frequently occurs in a subclinical form and may be associated with not only previously identified "high-risk" HPV types such as type 16, but also with the HPV type 42 that has not previously been considered as oncogenic.

Detection of human papillomavirus infection in tissue blocks by in situ hybridization as compared with a polymerase chain reaction procedure

Tissue blocks from 25 cases of condyloma and/or dysplasia were used for human papillomavirus typing with DNA in situ hybridization, compared with the very sensitive polymerase chain reaction. Only one of these cases was negative with both methods: a case of vaginal "koilocytosis." Polymerase chain reaction, as expected, was the more sensitive method, positive in 24 cases, with seven double infections. In situ hybridization was positive in 18 cases, with only two detected double infections. There was excellent agreement between the two methods in typing results. In all cases in situ hybridization showed a positive reaction in areas of koilocytosis and/or dysplasia.